Improvement of Solubility and Dissolution Rate of Indomethacin by Solid Dispersion in Polyvinyl Pyrrolidone K30 and Poloxomer 188

The aim of this study was to prepare and characterize solid dispersion (SD) of indomethacin (INDO) with polyvinyl pyrrolidone K30 (PVP) and poloxamer 118 (POLO) for enhancing its dissolution rate and bioavailability. The SDs of INDO was prepared by solvent evaporation method. The SDs was evaluated for practical yield, drug content, saturation solubility and in vitro dissolution study, Scanning electron microscopy (SEM), X-ray powder diffractometry (XRPD) and differential scanning calorimetry (DSC). The dissolution rates in PVP and POLO SDs were much faster than the pure INDO or physical mixtures (PM). The data from the XRPD showed that the drug was crystalline in all PMs. Significant change in melting peak in DSC thermograms of SDs revealed amorphization. SDs showed marked increase in the solubility of INDO with carrier concentration. At the highest ratio of carriers the drug solubility was enhanced about 6-folds and 3-folds for SD in POLO and in PVP, respectively. The dissolution rate was increased with carrier concentration at pH 7.4. XRPD data revealed a remarkable interaction between the INDO and the carrier that enhanced drug dissolution. The 1:10 ratio of POLO was sufficient for conversion of INDO to amorphous form.